{ "openapi": "3.1.1", "info": { "title": "How Long Will It Last? API", "version": "1.0.0", "summary": "Estimate remaining life of appliances and home components and plan the replacement.", "description": "Every endpoint performs the same calculation as the human page and returns inputs, result, units, assumptions, sources, warnings and computedAt. MCP endpoint: /mcp." }, "servers": [ { "url": "https://howlongwillitlast.usefulweb.site" } ], "paths": { "/api/v1/calculate": { "post": { "operationId": "calculate", "summary": "Estimate remaining life of appliances and home components and plan the replacement.", "description": "Pick an appliance or home component, enter its age, how hard it is used and how well it is maintained. The tool uses the life-expectancy ranges published in InterNACHI's Standard Estimated Life Expectancy Chart for Homes to estimate remaining years, the share of life used, and a replacement planning window.\n\nMethodology:\n- Base range: the YEARS value for the item from InterNACHI's Standard Estimated Life Expectancy Chart for Homes (e.g. '9 to 13'). Single values use the same min and max; 'N+' values are open-ended (only a minimum).\n- Adjusted range = base range × usage multiplier (light 1.15, normal 1.0, heavy 0.8) × maintenance multiplier (regular 1.0, occasional 0.9, neglected 0.75). These multipliers are this tool's own assumptions, not published figures; InterNACHI's values already assume regular recommended maintenance and normal wear and tear.\n- Remaining years = max(0, adjusted min − age) to max(0, adjusted max − age).\n- Life used = age ÷ midpoint of the adjusted range × 100 (open-ended: ÷ adjusted minimum).\n- Status: < 50% early life, 50–80% mid-life, ≥ 80% but below adjusted minimum approaching end, between adjusted min and max within end-of-life range, beyond adjusted max beyond expected life.\n- Replacement window = current year + remaining min … current year + remaining max (rounded to whole years).\n\nLife expectancies are guidelines only, not guarantees or warranties (InterNACHI).", "tags": [ "everyday" ], "x-mcp-tool": "how_long_will_it_last", "requestBody": { "required": true, "content": { "application/json": { "schema": { "$ref": "#/components/schemas/HowLongWillItLastInput" }, "examples": { "example1": { "summary": "7-year-old refrigerator, normal use", "value": { "item": "refrigerator", "ageYears": 7, "usage": "normal", "maintenance": "good" } }, "example2": { "summary": "10-year-old water heater, heavy use, occasional maintenance", "value": { "item": "water-heater", "ageYears": 10, "usage": "heavy", "maintenance": "average" } }, "example3": { "summary": "4-year-old washing machine, light use", "value": { "item": "washing-machine", "ageYears": 4, "usage": "light", "maintenance": "good" } } } } } }, "responses": { "200": { "description": "Calculation result envelope.", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/HowLongWillItLastResult" } } } }, "400": { "description": "Malformed JSON body.", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } }, "422": { "description": "Invalid input (see errors[]).", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } }, "429": { "description": "Rate limit exceeded (see Retry-After).", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } } } } }, "/api/v1/tool": { "get": { "operationId": "getToolDefinition", "summary": "Inputs, output schema and examples for this tool", "responses": { "200": { "description": "Tool definition.", "content": { "application/json": { "schema": { "type": "object" } } } } } } } }, "components": { "schemas": { "Problem": { "type": "object", "description": "RFC 9457 problem details. 422 responses include per-field `errors`.", "required": [ "type", "title", "status", "detail" ], "properties": { "type": { "type": "string" }, "title": { "type": "string" }, "status": { "type": "integer" }, "detail": { "type": "string" }, "code": { "type": "string" }, "errors": { "type": "array", "items": { "type": "object", "required": [ "field", "message" ], "properties": { "field": { "type": "string" }, "message": { "type": "string" } } } } } }, "HowLongWillItLastInput": { "type": "object", "additionalProperties": false, "properties": { "item": { "title": "Item", "type": "string", "enum": [ "air-conditioner-window", "trash-compactor", "dehumidifier", "dishwasher", "food-waste-disposal", "dryer-vent-plastic", "dryer-vent-steel", "clothes-dryer", "exhaust-fans", "freezer", "gas-oven", "hand-dryer", "humidifier-portable", "microwave-oven", "range-hood", "electric-range", "gas-range", "refrigerator", "swamp-cooler", "washing-machine", "whole-house-vacuum", "caulking", "paint-exterior", "paint-interior", "stains", "entertainment-center", "kitchen-cabinets", "countertop-laminate", "countertop-cultured-marble", "deck-planks", "deck-composite", "door-vinyl-exterior", "door-hollow-core", "afci", "light-fixtures", "propane-backup-generator", "service-panel", "solar-panels", "solar-batteries", "electrical-accessories", "carpet", "laminate-flooring", "vinyl-flooring", "linoleum", "garage-door", "garage-door-opener", "co-detector", "security-system", "central-ac", "boiler", "ceiling-fan", "condenser", "furnace", "gas-fireplace", "heat-pump", "whole-house-humidifier", "thermostat", "burner", "faucets", "fiberglass-tub-shower", "tankless-water-heater", "shower-doors", "sump-pump", "toilet-tank-components", "water-heater", "water-softener", "well-pump", "roof-asphalt-architectural", "roof-asphalt-3-tab", "roof-metal", "roof-epdm", "vinyl-siding", "asphalt-driveway", "wood-fencing", "pool-filter-pump", "pool-water-heater", "pool-vinyl-liner", "windows-double-pane", "windows-vinyl", "skylights", "window-glazing" ], "default": "refrigerator" }, "ageYears": { "title": "Current age", "type": "number", "minimum": 0, "maximum": 200, "default": 5, "x-unit": "years" }, "usage": { "title": "Usage intensity", "type": "string", "enum": [ "light", "normal", "heavy" ], "default": "normal" }, "maintenance": { "title": "Maintenance quality", "type": "string", "enum": [ "good", "average", "poor" ], "default": "good" } }, "required": [ "ageYears" ] }, "HowLongWillItLastResult": { "type": "object", "additionalProperties": false, "required": [ "schemaVersion", "tool", "computedAt", "inputs", "summary", "result", "units", "assumptions", "sources", "warnings", "presentation", "links" ], "properties": { "schemaVersion": { "type": "string", "const": "1.0" }, "tool": { "type": "object", "additionalProperties": false, "required": [ "id", "name", "version" ], "properties": { "id": { "type": "string" }, "name": { "type": "string" }, "version": { "type": "string" } } }, "computedAt": { "type": "string", "format": "date-time" }, "inputs": { "type": "object", "description": "Normalised inputs actually used, including applied defaults." }, "summary": { "type": "string" }, "result": { "type": "object", "additionalProperties": false, "required": [ "item", "category", "publishedYears", "publishedMin", "publishedMax", "openEnded", "factor", "adjustedMin", "adjustedMax", "ageYears", "remainingMin", "remainingMax", "lifeUsedPercent", "status", "replacementWindowStart", "replacementWindowEnd" ], "properties": { "item": { "type": "string" }, "category": { "type": "string" }, "publishedYears": { "type": "string", "description": "Verbatim value from the InterNACHI chart." }, "publishedMin": { "type": "number" }, "publishedMax": { "type": [ "number", "null" ], "description": "null for open-ended values like \"20+\"." }, "openEnded": { "type": "boolean" }, "factor": { "type": "number", "description": "Usage multiplier × maintenance multiplier (tool assumption)." }, "adjustedMin": { "type": "number" }, "adjustedMax": { "type": [ "number", "null" ] }, "ageYears": { "type": "number" }, "remainingMin": { "type": "number" }, "remainingMax": { "type": [ "number", "null" ] }, "lifeUsedPercent": { "type": "number", "description": "Age ÷ midpoint of the adjusted range (÷ adjusted minimum if open-ended) × 100." }, "status": { "type": "string", "enum": [ "early-life", "mid-life", "approaching-end", "within-end-of-life-range", "beyond-expected-life" ] }, "replacementWindowStart": { "type": "integer", "description": "Calendar year when the adjusted minimum life is reached (start budgeting)." }, "replacementWindowEnd": { "type": [ "integer", "null" ], "description": "Calendar year when the adjusted maximum life is reached." } } }, "units": { "type": "object", "additionalProperties": { "type": "string" } }, "assumptions": { "type": "array", "items": { "type": "string" } }, "sources": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "title" ], "properties": { "title": { "type": "string" }, "url": { "type": "string" }, "publisher": { "type": "string" }, "retrievedAt": { "type": "string" }, "note": { "type": "string" } } } }, "warnings": { "type": "array", "items": { "type": "string" } }, "presentation": { "type": "array", "items": { "type": "object" }, "description": "Display blocks used by the human page (same data)." }, "links": { "type": "object", "additionalProperties": false, "required": [ "human", "api", "openapi", "methodology" ], "properties": { "human": { "type": "string", "format": "uri" }, "api": { "type": "string", "format": "uri" }, "openapi": { "type": "string", "format": "uri" }, "methodology": { "type": "string", "format": "uri" } } } } } } } }